I need to test the hypothesis that the amount of rainfall doesn't affect the yield of a crop. Other predictor variables in the model I have to use are the variety of crop and the soil that the crop is planted in. I have found the ANOVA table with the residuals and regression, and also got one where there are residuals and all of the variables listed separately.
I have set $H_0$ to be that the coefficient of the rainfall in the model is equal to $0$, with $H_1$ being that it doesn't equal to $0$.
To find the p-statistic, do I need to find the F-value of just the rainfall and the residuals, or of all of the predictor variables together and the residuals. Are my hypothesis the right way around or do I need to switch them?
EDIT: I am now checking if the soil has made a difference to the crop yield. The soil has a value of 1 if it was grown in clay, and 0 otherwise. When using t.test(yield~ soil), I get a different value to the p value in the ANOVA? Is this an issue?